Intsia bijuga (formerly Afzelia bijuga syn. Afzelia australis), I. palembanica. Family: Leguminosae
Johnstone River teak; Scrub mahogany (North Queensland); Merbau (Malaysia); Vesi (Fiji); Moluccan ironwood (United Kingdom); Go-nux (Vietnam); Ipil (Philippines); Hintzy (Madagascar); Melila, Bendora (Papua New Guinea); Lumpho, Lum-paw, makamong (Thailand); Kivoli, Vuvula (Solomon Islands)
- Large hardwood tree
- Grows to 40m high
- Trunk is 0.6m diameter
- Often a bushy tree forming a spreading canopy
- Johnstone River and Daintree areas of North Queensland
- Papua New Guinea
- Solomon Islands
- New Caledonia
- Heartwood yellowish-brown or orange-brown when first cut, turning darker with age to brown or deep reddish-brown
- Sapwood white, pale yellow or buff and sharply distinct from heartwood
- Grain varies but usually interlocked or wavy.
- Texture is coarse but even.
- Attractive figure (pattern) on back-sawn material.
- Cross arms
- Bridge building
- Mining timbers
- General construction
- Quality furniture, outdoor furniture
- Turnery, parquetry
- Boat building (especially for decking)
- Musical instruments
- Tool handles
- Density: 830kg/m3 at 12% moisture content; about 1.2m3 of seasoned sawn timber per tonne.
- Strength groups: S2 unseasoned, SD3 seasoned.
- Stress grades: F11, F14, F17, F22 (unseasoned), F14, F17, F22, F27 (seasoned) when visually stress-graded according to AS 2082—2000: Timber—Hardwood—Visually stress-graded for structural purposes.
- Joint groups: J3 unseasoned; JD2 seasoned.
- Shrinkage to 12% MC: 2.6% (tangential), 1.2% (radial).
- Unit shrinkage: 0.30 % (tangential) 0.19 % (radial)—these values apply to timber reconditioned after seasoning.
- Durability above-ground: Class 1 (life expectancy more than 40 years).
- Durability in-ground: Class 3 (life expectancy 5–15 years).
- Lyctine susceptibility: untreated sapwood susceptible to lyctid borer attack.
- Termite resistance: resistant.
- Preservation: sapwood readily impregnates with preservative.
- Seasoning: seasons well with kiln or air-drying, with little degrade and very little shrinkage or movement.
- Hardness: hard (rated 2 on a 6-class scale) to indent and work with hand tools.
- Machining: working properties vary; cuts cleanly but may blunt or gum cutting edges; cutting angle should be reduced to 20° when planing quarter-sawn stock; turns well.
- Fixing: can split unless pre-bored, but holds fastenings well.
- Gluing: glues satisfactorily except with casein glues.
- Finishing: paints, stains and polishes well, but gum bleed-through or oily patches may affect the finish.
- Sapwood: sharply distinct from the heartwood
- Heartwood: dark red-brown or yellow-brown
- Texture: coarse and even; grain often interlocked
- Vessels: moderately large, visible to naked eye; short radial pairs or multiples and solitary cells; often visible sulphur yellow and dark-coloured deposits; vessel lines prominent on longitudinal surfaces
Research and resources
- Boland, DJ, Brooker, MIH, Chippendale, GM, Hall, N, Hyland, BPM, Johnston, RD, Kleinig, DA and Turner, JD 2006, Forest trees of Australia, 5th ed., CSIRO Publishing, Collingwood, Australia.
- Bootle, K 2005, Wood in Australia: Types, properties and uses, 2nd ed., McGraw-Hill, Sydney.
- Ilic, J 1991, CSIRO atlas of hardwoods, Crawford House Press, Bathurst, Australia.
- Queensland Government, DAF 2018, Construction timbers in Queensland: properties and specifications for satisfactory performance of construction timbers in Queensland. Class 1 and Class 10 buildings, Books 1 & 2, Department of Agriculture and Fisheries, Brisbane.
- Standards Australia, 2000, AS 2082—2000: Timber—Hardwood—Visually stress-graded for structural purposes, Standards Australia International, Strathfield, NSW.
- Last reviewed: 12 Dec 2018
- Last updated: 12 Dec 2018